Use of a prostate model to assist in training for digital rectal examination.

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OBJECTIVES: To assess the accuracy of prostate size estimation on digital rectal examination (DRE) before and after training with a three-dimensional prostate model relative to prostate volume by transrectal ultrasound (TRUS).

METHODS: A total of 100 subjects underwent DRE by one of four family physicians (FP1, n = 34; FP2, n = 26; FP3, n = 22; and FP4, n = 18). One half were examined before any training on DRE prostate size examination and one half after the physicians were trained. Training involved teaching with a three-dimensional prostate model having posterior surface areas corresponding to the average dimensions of six different prostate volumes. The FPs were instructed to estimate the prostate size on the DRE to the nearest 5 g. A single urologist unaware of the DRE results performed TRUS on all patients to measure the prostate volume.

RESULTS: Before training, the DRE size estimates ranged from 10 to 100 g (mean +/- SD 32.8 +/- 21.6), with a TRUS volume of 11 to 122 g (mean +/- SD 38.9 +/- 23.1). The correlation between the DRE and TRUS estimates was 0.25, suggesting low agreement (intraclass correlation coefficient [ICC] 0.35, 95% confidence interval 0.31, 0. 38). After training, 50 different patients had DRE size estimates of 10 to 100 g (mean +/- SD 39.4 +/- 19.7) and TRUS volume of 10 to 119 g (mean +/- SD 41.5 +/- 24.1). The correlation between the techniques was higher in patients examined after training (r = 0. 765), suggesting much better agreement between the techniques (ICC 0. 87; 95% confidence interval 0.86, 0.88). Among the physicians, agreement between DRE and TRUS was higher after training (ICC 0.64 to 0.96) than before training (ICC 0.02 to 0.49).

CONCLUSIONS: Although the subjects examined before and after training differed, the agreement between TRUS and DRE prostate size estimates by the FPs appeared to be stronger after training with a three-dimensional prostate model. This model may be a useful tool to assist in training FPs and medical students to measure prostate size on DRE.





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Medicine and Health Sciences




Department of Medicine

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